In the present age, Java programs are executed on a variety of information apparatuses. A virtual machine for executing Java programs, known as a JavaVM, is incorporated on a digital TV, a personal computer, a mobile phone, and the like, and executes Java programs.
A function of executing a Java program in an existing digital television is disclosed in Japanese Patent National Publication No. 2003-504753. FIG. 1 is a diagram showing an example configuration of an existing digital television for executing a Java program in which an application manager is implemented in order to manage an application that is loaded via a digital television receiver. A digital TV receiver 3002 receives a broadcast data stream 3021 by a signal monitor 3013. The signal monitor 3013 notifies, to an application manager 3012, whether there is an application being a Java program included in the broadcast data stream 3021 through signal data 3022. The application manager 3012 loads and executes the application using the signal data 3022. When the application is executed, display information is provided from a display manager 3011 in the form of a display context 3023. Furthermore, the display manager 3011 provides appropriate display information to a television monitor 3001.
The application manager 3012, which operates in accordance with a rule 3014, shifts the state of the application to state load, state pause, state active, and state delete. Examples of the rule include “only one application is activated at one time” and “only one application is displayed at one time.”
However, the existing technique has a problem that it takes long from when a Java program is executed until when a user can actually receive its function. There are some reasons for it. First, in order to execute a Java program, the JavaVM is required to be activated prior to such execution, but in general, it takes time for a Java VM to get activated. Furthermore, it also takes time until the download of a Java program completes. In a digital TV and an information apparatus and the like, it takes time from when a Java program is decided to be activated until when it is actually activated completely, since time for performing such processing and waiting time are included. Particularly, in an information apparatus in which a Java program is automatically downloaded and executed at power on time, there is time during which nothing is displayed lasts for a while after the power is turned on, which causes a problem that the user becomes anxious. This problem is especially notable in information home appliances such as digital TVs whose CPU processing speed is not so high.
By implementing, as an embedded program, a partial function which is originally supposed to be carried out by a Java program and by executing it while Java program is being activated, the present invention aims at shortening, for the viewer, the time required for start-up processing, and at further providing an information provision unit, between the embedded program and the Java program, that enables the Java program to run in a consistent manner by inheriting the action state of the embedded program upon the completion of starting up the Java program.